Filter bag coupling



Patented Apr. 29, 1952 T OFFICE FILTER BAG COUPLING George A. Brace, Highland Park, 111., assignor to The Hoover Company, North Canton, Ohio, a

corporation of Ohio Application September 8, 1949, Serial No. 114,669

11 Claims. 1

for removal in a very simple and expeditious manner.

It is an object of the invention to provide a new and improved filter coupling for a suction cleaner.

More specifically it is an object of the invention to provide a simple unitary self-acting bag coupling for positively connecting the inlet end of a filter bag to the exhaust of a suction cleaner in an airtight manner.

Still another object of the invention is to provide a self-acting expanding clamp the gripping power of which increases automatically as the force tending to remove it increases.

A further object of the invention is to provide a self-acting clamp in which the force required to release it is many times smaller than the normal gripping force of the clamp.

A still further object of-the invention is to provide a self-actingclamp so constructed and arranged that it offers very little resistance to the insertion of a filter bag and very high resistance to the removal of the bag therefrom.

These and other objects will appear more fully upon reading the following specification and claims and upon considering the attached drawings illustrating several embodiments of the invention. Referring now to the drawings:

Figure 1 is a side view of a suction cleaner illustrating one embodiment of the invention with certain parts broken away;

Figure 2 is an enlarged partial sectional view of the coupling shown in Figure 1;

Figure 3 is a partial sectional view of a second embodiment of the invention and showing the filter inlet almost withdrawn from the coupling; and

Figure 4 is a vertical view partly in section of a third embodiment of the invention which includes a convenient push button operator for releasing the filter from the coupling.

This application is a continuation of my application for United States Letters Patent Serial No. 31,319 filed June 5, 1948.

Referring now to the drawings it will be observed that Figure 1 shows a conventional floor type suction cleaner HJ having across its front a suction nozzle II and a motor-driven agitator roll I2. An upright motor not shown drives a directly coupled suction fan I3, while the agitator is driven by a belt [4.

Although the entire cleaner is not illustrated, it will be understood that it is of conventional form having the usual operating handle [5 pivoted to the rear of the cleaner body. The body is supported by the usual front wheels l6 and rear wheels ll. As is customary, the fan exhaust discharges at the rear end of the cleaner body. Detachably connected to this discharge port is the novel coupling 18 constituting an important feature of the present invention.

Coupling [8 comprises a generally tubular body portion 19 provided at its rear with a stepped; fiange 20 so that it can be detachably sealed to be the cleaner discharge passageway as by a pair of nuts 2|. Carried within a channel 22 at the discharge end of tube [9 is a self-acting clamp member of rubber or other like material- The waist of this clamp comprises an inwardly extending flange 23 adapted to fit in groove 22 and anchor the clamp on the adapter. A rela-- tively thin walled section 24 of the skirt interconnects fiange 22 with a relatively heavy rubber rim or ring 25 having the general contour illustrated in Figure 2. The outer peripheral surface of this ring carries a plurality of outwardly and rearwardly extending flanges 26 which are preferably somewhat thicker at their base. It is also desirable that the radial extent of thesefianges decrease slightly toward the rearmost portion of the clamp.

Annulus 25 is freely supported by thin-walled. section 24 and extends inwardly so that its inner lower corner is closely adjacent the cammed surface 21 surrounding the outer periphery of tube H).

In order to center the clamp and to insurethat all parts thereof are stressed normally outwardly there is carried upon the outer surface: of tube i9 a light metal ring 28 held in place by screws 29. This ring is formed of lightspring material and carries a plurality of resilient arms 30 the outer ends of which underlie and press lightly against the inner surface of annulus 25. These fingers serve not only to keep the clamp centered on the adapter but also prevent any tendency to the rings to deform inwardly and provide an air leak as will become more apparent below.

Referring more particularly to Figure 1, it will be seen that a filter bag, preferably of suitable paper construction, is indicated at 3|. Its lower end is pleated and formed to have an interior perimeter slightly less than the normal outer perimeter of the bottom rim of the self-actin rubber clamp. The inlet end preferably carries a tubular valve 32 the inner end of which extends freely into the interior of the bag for a suitable distance so as to prevent collected dirt from falling back into the cleaner body. The inlet of the bag may be reinforced by an outer wrapping of paper 34. In order to protect the filter 3| against damage and to aid in supporting it, there is provided an outer cloth appearance sack the lower end 36 of which may be detachably secured to the lower step of connectin flange 20.

As an aid in seating the inlet of the filter on the adapter or in removing it therefrom, use may be made of a manually operable removal ring which is attached to clamping ring and is accessible for distorting the latter without interfering with the removal or placement of the filter itself. As shown, this means comprises a removal ring 37 surrounding adapter tube l9 at a point between the cleaner body and the inlet of the filter. This ring may be connected to ring 25 by two or more arms 38 the inner ends of which are attached to clamping ring 25 as by being imbedded therein. It will now be clear that an operator, by grasping ring 3i and pulling axially rearwardly thereon, will deform ring 25 to which arms 38 are attached by pulling portions of the ring out of the plane of the ring proper. In so doing, portions of skirt 24 opposite arms 38 will be stretched and distorted and will act to restore the ring to its normal condition upon release of removal ring 37. Distortion of the self-clamping ring from its plane will reduce the normal diameter of the clamp and will also disturb the gripping action of flanges 25 against the interior of the filter neck.

Operation To place a filter on the coupling the operator opens zipper 39 on the lower side of the appearance bag and pushes ring 31 toward the cleaner body. Arms 38 connecting the ring to the rubber clamp cause the latter to become distorted and reduced in circumference. While holding ring 3"! in this position, the operator grasps the inlet neck of the filter and slides it on over thin sealing flange ii}, over skirt 24 and finally over ribs 26 which bend downwardly toward the rubber clamping ring 25. As soon as the bag is in proper position, ring 37 is released allowing the rubber clamp to resume its normal form in which it tightly grips and seals against the inner periphery of the filter neck in an airtight manner. Once the cleaner is placed in operation, the pressure within the bag will tend to force it oil the adapter. However, as the bag tends to move outwardly, ribs 26 will flare outwardly into tighter gripping relation with the filter. Moreover, ring 25 asa whole will move slightly forwardly to bring the inner lower cor-,- ner of the ring into engagement with cam surface 21. Further forward movement. of .the clamp will tend to pivot ring 25 outwardly into even tighter engagement with the bag neck. Thus, the greater the force tending to remove the bag, the greater the gripping and sealing action of the clamp.

If it is desired to remove the filter, it is merely necessary for the operator to again grasp ring 3'! and move it rearwardly toward the cleaner body a slight amount. It is found in actual practice that even slight distortion or movement of a part of the clamp will break the seal and release the filter for withdrawal from the mounting. In this connection, it is to be noted that skirt 24 should be thick enough to maintain ring 25 in normal shape and position but flexible enough to permit distortion in the removal operation and flexible enough to permit ring 25 to be brought freely into contact with cam surface 21.

The second embodiment is illustrated in Figure 3 in which parts similar to those in the first embodiment are designated by primed numerals. Since for the most part the component element in the two embodiments are substantially identical, it is not deemed necessary to make a detailed description thereof. It will be noted that the principal diiference resides in the construction and arrangement of removal ring 31' employed to deform the clamping ring 25' when inserting or removing the filter 31'. In the first embodiment the removal ring was entirely supported by the clamping ring through connector links 33-38. This is also true of the Figure 3 construction. However, it will be noted that links 38'38' flare outwardly toward their connection point with the clamping ring and cooperate with stops 45-% to collapse the rubber ring 25' inwardly toward the tube 19' and ring 31 is bowed rearwardly towards the cleaner body. Stops 45 may be formed as a part of arms- 30' and are so formed as to leave adequate operating room for fingers 38-38' as the same are flexed inwardly in operation.

The second embodiment operates in very much the same manner just described above in connection with the first embodiment with the exception that positive means are provided for forcing portions only of the clamping ring inwardly as it is moved rearwardly out of clamping relation with the filter neck. As in the first form, flange 40' on the outer end of the clamping ring not only functions to prevent dirt from interfering with the operation of the clamp but, of equal importance, it serves as a means for keeping the bag neck centered on the adapter. This additional support prevents the filter from tilting on the clamping ring and from becoming accidentally dislodged therefrom.

A third form of the invention is illustrated in Figure 4 and differs from Figure 3 primarily in the provision of a, push button operator for the removal ring. Elements corresponding to those in the first embodiment are indicated by the same numerals primed. Removal ring 3'! is supported by and connected to the clamping ring 25 by two or more cammed spring-like arms 38. Arms 38' are biased outwardly and perform the function of resilient fingers 38 of the second embodiment. Stops 45' mounted on tube 19' overlie arms 38' and cause the arms to move inwardly as removal ring 31' is moved axially rearwardly. During this operation parts of ring 25 are flexed inwardly to release the filter bag.

The manual operator for the removal ring comprises a. push button carried by support 41 formed at the top of connector flange 20. Surrounding the stem of the push button is a compression spring 48 normally urging the button outwardly. A fork 49 is mounted upon the lower side of the button stem and straddles the adapter tube. The lower end of this fork terminates adjacent beveled abutments 50-50 carried by removal ring 37. As-will be manifest, when button 46 is depressed, the ends of the fork will over-ride the cammed surface of the abutments 5050 and force the removal ring rearwardly causing distortion of the clamping ring. Under these circumstances the filter may be readily removed or inserted upon the coupling device. Release of the button allows the clamping ring to resume its expanded position either in contact with the filter or, if one is not in place, ready to receive one at a later time.

While the various modifications of this invention have been described in connection with a destroyable paper filter, it will be obvious that it has equal utility with a cloth filter, particularly if the inlet end thereof has been reinforced to prevent it from stretching when in position. While only three arrangements of parts have keen illustrated and described, it will be obvious that various other arrangements can be employed without departing from the principles or spirit of this invention.

It must be understood that the protection herein applied for is not confined to the particular combination of features or elements set out in the following claims. Protection is herein applied for for any one or more of the features or elements referred to in the following claims or described in the foregoing specification or shown in the accompanying drawings either independently or in combination.

What I claim is:

1. A bag mounting for a suction cleaner filter bag comprising a tubular member adapted to be connected to the discharge passage of a suction cleaner, a self-acting clamp for the inlet of a filter bag associated therewith comprising a flexible resilient skirt-like member, said skirtlike member including an upper waist portion carried by said tubular member, a lower thickened rim of greater periphery than said waist portion and an intermediate relatively thinwalled flexible portion interconnecting said waist and lower rim and adapted to support the latter in spaced relation to said tubular member, said lower rim being adapted to grip the inlet neck of a filter bag firmly and in an airtight manner, and said tubular member being provided with a camming surface positioned to flare the lower rim of said skirt-like member outwardly into firmer gripping relation to a, filter bag when said rim is moved axially toward said waist.

2. A bag mounting as claimed in claim 1 including means operable to move a portion of said rim away from said camming surface and thereby distort it sufficiently to release the inlet of a filter bag.

3. A bag mounting for a suction cleaner filter bag comprising av flexible resilient. skirt-like tubular member having a waist at one end and a flanged rim at its other end, said flanged rim including a thick inwardly extending portion and a plurality of relatively thin outwardly extending circumferential ribs, means supporting said waist and normally spaced from said inwardly extending flange, and cammed means positioned to flare said flanged rim outwardly upon axial movement thereof whereby said skirtlike member grips tightly the inlet neck of a filter bag.

4. A bag mounting as claimed in claim 3 in which said cammed means is so positioned with respect to said flanged rim that the pressure within a fllter bag supported thereon tends to expand said rim into tighter gripping action on the inlet of said filter.

5. A bag mounting as claimed in claim 3 including manually operable means for deforming said flanged rim to facilitate the placement or removal of a filter bag.

6. A bag mounting for a suction cleaner filter bag comprising a resilient flexible skirt-like tubular member including a waist portion at one end, a flanged rim at the other end adapted to form a. self-acting clamp to grip the inlet end of a filter, a relatively thin walled portion inter-connecting said waist and rim, a tubular member within and supporting said waist, and resilient means underlying said flanged rim and urging it radially outward.

'7. A bag mounting as claimed in claim 6 ineluding manually operable means connected to the flanged rim of said tubular member for distorting said flanged rim out of gripping relation to the inlet of a filter bag.

8. A bag mounting for a suction cleaner filter bag comprising a tubular member adapted to be connected to the discharge passage of a suction cleaner, a self-acting clamp for the inlet of a filter bag associated therewith comprising a flexible resilient skirt-like member, said skirt-like member including a waist portion adapted to seat on said tubular member in an airtight manner, a thickened rim portion and a thin-walled portion interconnecting said waist and said rim, said rim being constructed and joined to said thin-walled portion so as to collapse inwardly slightly when the neck of a filter bag is telescoped over said skirt-like member from the waist end thereof and to expand outwardly into firm gripping engagement with said neck upon a movement tending to withdraw said filter bag.

9. A bag mounting for a suction cleaner filter bag comprising a tubular member adapted to be connected to the discharge passage of a suction cleaner, a self-acting clamp for the inlet end of a filter bag associated therewith comprising a flexible resilient skirt-like member, said skirt-like member including a waist portion, a thickened rim and a relatively thin-walled portion interconnecting said rim and said Waist, the outer surface of said thickened rim having a generally frusto conical shape formed by closely spaced annular flanges of progressively increasing diameters, said thin-walled portion being connected to said thickened rim inwardly of the periphery of said rim whereby insertion of a filter neck over said self-acting clamp tends to collapse said rim inwardly while Withdrawal of said filter in a reverse direction tends to expand said rim into tight gripping engagement with the filter neck.

10. A bag mounting for a suction cleaner as defined in claim 9 in which the bases of said flanges are thicker than the outer peripheral edges thereof.

11. A bag mounting for a suction cleaner as defined in claim 9 in which said flanges on said thickened rim are inclined to the axis of said skirt-like member.

GEO. A. BRACE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,250,285 White July 22, 1941 2,321,778 Stout o- June 15, 1943 2,366,067 Smith Dec. 26, 1944 

